JMX-ify Scheduler implementations

[sbordet]

Jetty version
9.4.x

Description
Scheduler implementations lack JMX annotations.
Would be useful to know the scheduler name, the number of scheduler threads, whether it is daemon, etc.

[rk1165]

Hi @sbordet ,
How can I work on this, can you please guide me?
I have already cloned the project, signed the contributor agreement and subscribed to the mailing list. Is there anything else I need to do?

Also, please let me know if there's any prerequisite I need to read up or anything.

[sbordet]

@rk1165 thanks for volunteering!

Please read the contributor guidelines: https://github.com/eclipse/jetty.project/blob/jetty-10.0.x/CONTRIBUTING.md

In particular you have to make sure your commits are signed-off (the other requirement was the ECA, but you already signed it).

Then please have a look at how QueuedThreadPool is annotated with Jetty JMX annotations, and do something similar for ScheduledExecutorScheduler.

Please work against the jetty-9.4.x branch, make your changes, and then issue a pull request, electing me as a reviewer.

Let me know here if you need more help. Thanks!

[rk1165]

Hi, @sbordet
I made the aforementioned changes and raised the following PR #5821
Can you please review?